A tour of the Cell
Chapter 7 http://www.youtube.com/watch?v=o1GQyciJaTA&feature=related http://www.ibiblio.org/virtualcell/textbook/chapter3/chapter3.htm
http://vcell.ndsu.edu/animations/


All living things are composed of cells

Cells are the basic unit of function and structure in living things

All cells come from pre-existing cells

Eukaryotic vs. prokaryotic cells

Contains nucleus

Many organelles present

10-100 micrometers

Appeared later in the fossil record

Lacks a nucleus

Lacks organelles

1-10 micrometers

Appeared earlier in the fossil record

Two Basic types
Cell membrane cytoplasm
Prokaryote
Eukaryote
Cell membrane cytoplasm nucleus
Cell organelles

Compare and Contrast
Prokaryotes Eukaryotes
Cell membrane
Ribosomes
Nucleus
Endoplasmic reticulum
Golgi apparatus
Lysosomes
Vacuoles
Mitochondria
Cytoskeleton

Page 206

Compare/contrast plant and animal cells
Plant cell
Cell wall
Large vacuole chloroplast ribosomes mitochondria
Golgi apparatus
Endoplasmic reticulum
Cell membrane nucleus
Animal cell
Centrioles flagellum


Composed of proteins and a type of lipid called phospholipid

The structure that makes the plasma membrane is called the phospholipid bilayer http://www.wisc-online.com/Objects/construction-of-the-cell-membrane/

Phospholipid molecule of Plasma
Membrane

Plasma Membrane Structure

Ways cells get molecules in and out of cell
No cell energy used
Diffusion
Facilitated diffusion
Cell energy used
Active transport http://www.wisc-online.com/Objects/construction-of-the-cell-membrane/


The net movement of particles of a substance from where they are more concentrated to where they are less concentrated

Diffusion


The random movement of molecules from a high concentration to a low concentration
If system is left alone the molecules will eventually spread themselves equally every where – the molecules do not stop moving through

Types of Transport through plasma membrane

Passive transport

– Diffusion: some molecules cross the plasma membrane with no expenditure of energy or help from transport proteins

Osmosis: diffusion of water through a membrane
– Facilitated diffusion: Transport proteins provide a pathway for certain molecules to pass
Active transport

Water moves from high concentration to low concentration

What happens to a red blood cell when it is placed in water with different concentrations of salt?

Results of water movement on cells – Osmotic Pressure



Types of Transport through plasma membrane
Passive transport
– Diffusion

Osmosis
– Facilitated diffusion
Active transport: A transport protein pumps a solute across a membrane in the opposite direction to the way it travels with diffusion. It requires chemical energy.

Bulk Transport


For larger molecules and solid clumps of material the cell uses


Endocytosis – cell takes in materials in by infoldings in the membrane

Phagocytosis
Exocytosis – cell releases materials through membrane http://www.ibiblio.org/virtualcell/textbook/chapter3/cmf4a.htm
http://www.youtube.com/watch?v=aWItglvTiLc

Main cell parts and functions

Cytoplasm: holds organelles
- transport medium

Nucleus: Control center – contains the DNA (genetic material)

Ribosomes: make proteins

Ribosome

RER: modify and transport proteins

SER: Production of lipids
(fats)

Golgi apparatus: Process and package proteins and lipids

Chloroplast: Where photosynthesis occurs

Mitochondria: Release energy usable by the cell

Lysosome: Breaks down macromolecules into particles the cell can use

Homeostasis
( homeo_ =same
_stasis =standing still)
Unicellular organisms as well as cells in multicellular organisms must maintain homeostasis , or that is to say, relatively constant physical or chemical conditions.


Unicellular organisms
Multicellular organisms

To maintain Homeostasis


Unicellular organisms
– Grow
– Respond to environment
– reproduce
Multicellular organisms
– Have specialized cells that communicate with each other

Examples of Homeostasis in humans


Thermoregulation
Glucose regulation

Cell Specialization

In multicellular organisms there is a division of labor among the specialized cells

cell
Levels of Organization organ system tissue organ organism

Homeostatic loops http://www.youtube.com/watch?v=jkioZCDHT_E&list=PL7A750281106C
D067&index=38

Examples of Homeostasis in humans